1. Field
The fields of optical linear scanning and computed radiography systems include optical scanning systems for reading, inspecting, writing, and printing at high speed with high resolution and across wide ranges or formats.
2. Prior Art
Scanning at a very high speed along very wide scan ranges (on the order of magnitude of up to 1 m and even more) with very high resolution is needed in the fields of reading, inspecting, writing, and printing of and on Liquid Crystal Displays (LCDs), flat panels, High Definition Televisions (HDTVs) and plasma displays which are have a very wide format and need to be written and inspected with very high resolution.
The current systems for direct writing and imaging include a very large lens that covers the whole scanning area. Such a lens must have very high quality to enable high resolution and is extremely expensive. Accordingly, a scanning system that includes a small moving lens has an advantage. However, such a scanning system that scans at a very high speed along very wide ranges is not available yet.
The requirement for linear scanning at a high speed along wide ranges dictates the need for moving system that can work with the high accelerations associated in the direction changes of the scan when the scanning head moves back and forth.
U.S. Pat. No. 6,735,005 to Karin et al., entitled “Cartesian scanning system”, May 11, 2004, discloses a linear scanning system including a moving head that receives collimated beam to reflect this beam as a focused beam onto a scanned surface.
US published patent application of Karin et al., entitled “Scanning mechanism for high-speed high-resolution scanning”, May 11, 2004, Nr. 2004/0165923, discloses a mechanism for the moving system of the scanning head of the Karin et al. US patent.
While these scanning systems include a moving head consisting of a small lens, they are not suitable for high speed scanning along very wide format for the following reasons:                1. They use linear sliding which is associated with vibrations, motions that may not be smooth, and may entail grinding of the linear slide along the scanning range.        2. They were designed for the field of wafer inspection. In this field the spatial resolution of the moving scanning head should be in the range of sub-micrometers and thus is not capable of scanning along a very wide scanning range since such a spatial resolution of the position of the head cannot be achieved along a wide scanning range.        3. They are much slower than is needed for scanning wide ranges.        4. They can not adjust and hold the high accelerations that occur when the wide scanning systems change the direction of the scan.        5. They can not balance the vibrations produced at very high speeds.        6. They do not work with a smooth motion.        